Gastric Cancer – A Case Study

Mr Tan, a 60 year old Chinese gentleman and a smoker, came to see me for ‘gastric’ pains associated with food on and off for the past 20 years and loss of weight over the past one year. But he had never seen a doctor. He was well, but thin.

Examination of his abdomen revealed a firm lump where his stomach was. I recommended that he undergo urgent Gastroscopy, which revealed that he had a 5 cm malignant gastric ulcer in the lower part of his stomach. He also had Helicobacter pylori infection in his stomach.

Is Mr Tan’s gastric cancer common?

Stomach or gastric cancer is the 4th most common cause of cancer worldwide, but because it is frequently fatal, it is the 2nd most common cause of cancer death. It is more common in men and in developing countries. Gastric cancer can be divided into those in the upper stomach (proximal type) and lower stomach (distal type). Whereas the distal type is becoming less common, the proximal type is making up for this by becoming more common. Distal gastric cancer predominates in developing countries and in lower socio-economic groups, whereas proximal tumors are more common in developed countries and in higher socio-economic classes.

What are the risk factors for gastric cancer?

Men are more prone to gastric cancer than women. Mr Tan had Helicobacter pylori infection in his stomach and has probably had it for many decades, undetected. This bacterial infection causes chronic gastritis or persistent inflammation of the lining of the stomach and this is believed to be a direct cause of up to 80% of distal gastric cancers. Dietary risk factors are believed to include a high salt diet and preserved foods. There is a degree of genetic risk. Smoking and Blood group A are also associated with an increased risk as are people from lower social economic groups. A disease of the stomach called Pernicious Anaemia can also lead to gastric cancer. Severe acid reflux disease is associated with proximal gastric cancers. Those with some types of hereditary colonic polyps also have a higher risk.

Should everyone go for screening gastroscopy?

Although gastric cancer is more likely to be diagnosed in an older person, there is no evidence in most countries that routine endoscopic screening of the stomach makes any difference. The single exception is Japan which has the highest incidence of gastric cancer in the world, where routine screening has shown survival benefit. When patients come for screening colonoscopy for colon cancer (which is highly recommended at the age of 50 for average risk individuals), it makes sense to have gastroscopy at the same time to screen the stomach.

Then how could Mr Tan have had his cancer detected much earlier than this?

Unfortunately early gastric cancer has no symptoms and this is the reason why it is often diagnosed late and at an incurable stage. However, if there are symptoms such as upper abdominal discomfort or pain which persists, then investigations should be done. It is more urgent to be tested when there are ‘alarm symptoms’ such as loss of appetite and weight, vomiting, difficulty swallowing, vomiting of blood or passage of blood as black tarry stools. These are all symptoms of advanced disease. If Mr Tan had been investigated much earlier for his long-standing symptoms, perhaps his gastric cancer might have been found earlier. Even if there had not been a cancer then, but Helicobacter pylori was discovered years earlier, eradicating this infection with antibiotics might have reduced his chance of developing cancer.

What food, drink or other lifestyle habits could Mr Tan have avoided to prevent gastric cancer?

There is no absolute proof that food and drink are directly related to gastric cancer. However some studies suggest that a healthy diet with a lot of fresh fruits and vegetables while avoiding excessive salt and preserved food might be helpful. Smokers should certainly consider stopping. Anti-oxidants such as vitamin C and E have potential but unproven protective benefit. For patients with acid reflux, obesity should be avoided and alcohol makes reflux worse and therefore avoiding excessive alcohol could help prevent proximal cancers.

What tests did Mr Tan go through to detect his gastric cancer?

I performed Gastroscopy, which is the examination of the oesophagus, stomach and duodenum (first part of the small intestine) by means of a long flexible and steerable tube with lights and camera and the ability to pass small instruments through it to take biopsies or perform other minor surgical procedures. This is a very comfortable examination under sedation and allows the Endoscopist direct vision of the lining of the stomach. Cancers are often seen as large, deep ulcers with rolled and irregular edges. Early gastric cancers which are much more curable are seen as shallow or slightly protuberant lesions. Biopsies must be done to confirm the suspected diagnosis. At the same time a special test can be done to detect Helicobacter pylori infection. I also sent Mr Tan for a chest x-ray, and a PET-CT scan (Positron Emission plus Computerised Tomograms) to see if the cancer had spread to other parts of the body.

How was Mr Tan treated and what was his progress?

Very early cancers that are very superficial may nowadays be completely removed by Endoscopic Mucosal Dissection, that is stripping off the lining of the stomach containing the cancer through a Gastroscope. However, Mr Tan was found to have advanced cancer with secondary cancer in the liver and lungs. I therefore assembled a team of Surgeon, Oncologist and Radiotherapist to help me treat Mr Tan. The primary cancer was removed by surgery to prevent blockage in the stomach – partial removal of the stomach (sub-total gastrectomy). He had very few consequences of losing part of his stomach – he had to take smaller, more frequent meals and had to take iron and vitamin supplements, but he was otherwise able to eat reasonably well after surgery. Mr Tan also had chemotherapy and radiotherapy to try to remove cancer in other parts of the body. His prognosis unfortunately is guarded. Fewer than one in 10 patients like Mr Tan will survive at least 5 years. However if gastric cancer is found very early, up to 9 out of 10 patients survive at least 5 years.

I performed Gastroscopy, which is the examination of the oesophagus, stomach and duodenum (first part of the small intestine) by means of a long flexible and steerable tube with lights and camera and the ability to pass small instruments through it to take biopsies or perform other minor surgical procedures. This is a very comfortable examination under sedation and allows the Endoscopist direct vision of the lining of the stomach. Cancers are often seen as large, deep ulcers with rolled and irregular edges. Early gastric cancers which are much more curable are seen as shallow or slightly protuberant lesions. Biopsies must be done to confirm the suspected diagnosis. At the same time a special test can be done to detect Helicobacter pylori infection. I also sent Mr Tan for a chest x-ray, and a PET-CT scan (Positron Emission plus Computerised Tomograms) to see if the cancer had spread to other parts of the body.

How was Mr Tan treated and what was his progress?

Very early cancers that are very superficial may nowadays be completely removed by Endoscopic Mucosal Dissection, that is stripping off the lining of the stomach containing the cancer through a Gastroscope. However, Mr Tan was found to have advanced cancer with secondary cancer in the liver and lungs. I therefore assembled a team of Surgeon, Oncologist and Radiotherapist to help me treat Mr Tan. The primary cancer was removed by surgery to prevent blockage in the stomach – partial removal of the stomach (sub-total gastrectomy). He had very few consequences of losing part of his stomach – he had to take smaller, more frequent meals and had to take iron and vitamin supplements, but he was otherwise able to eat reasonably well after surgery. Mr Tan also had chemotherapy and radiotherapy to try to remove cancer in other parts of the body. His prognosis unfortunately is guarded. Fewer than one in 10 patients like Mr Tan will survive at least 5 years. However if gastric cancer is found very early, up to 9 out of 10 patients survive at least 5 years.